Management of neurologic disorders

Plasma-exchange in Chronic Peripheral Neurological Disorders

We investigated 19 patients affected by chronic peripheral neurological disorders treated with therapeutic plasma exchange (TPE) to verify the efficacy of the therapeutic protocol used in these diseases.

Every patient was clinically considered after 5 TPE. Those who showed an improvement started chemotherapy and continued TPE at the rate of 2 procedures/week for 2 weeks, then 1 procedure/week for 1 month and finally 1 procedure every 2 weeks for 2 months. Intravenous immunoglobulins (IVIg) were infused at the end of apheretic treatment in one of the patients affected by neurological disorders due to monoclonal gammopathy undetermined significance. HCV-positive patients with cryoglobulins were treated with α-interferon (α-IFN) for 6 months before TPE. Eleven patients (58%) had a symptomatic improvement, 2 (1.5%) stopped TPE treatment owing to side effects and 6 (31.5%) did not respond to apheretic therapy.

In order to improve the advantages of TPE we suggest using IVIg at the end of apheretic therapy, while in HCV-positive patients, at least one year of α-IFN therapy is required before initiating TPE.

American Society for Apheresis guidelines on the use of apheresis in clinical practice: practical, concise, evidence-based recommendations for the apheresis practitioner

The 6th Guidelines on the use of therapeutic apheresis in clinical practice published by the American Society of Apheresis provide practical, concise, and evidence based guidance for the apheresis medicine practitioner. The overall format of the Guidelines has remained unchanged with the 6th edition, compared to the 5th edition, with enhancements in the committee process of creating the guidelines. Because of changes in the writing committee structure, a number of changes have occurred in the ASFA category and recommendation grade for the use of apheresis in the treatment for a number of previously categorized clinical indications. In addition, eight new indications for apheresis, twenty three new clinical situations for previously categorized diseases, and ten new apheresis treatments for previously categorized disorders have been added. The 6th Guidelines continue to be an invaluable resource for those involved in apheresis medicine.

Clinical and immunologic characteristics of melanoma-associated retinopathy syndrome: eleven new cases and a review of 51 previously published cases

OBJECTIVE

To evaluate the signs, symptoms, and immune responses of patients with melanoma-associated retinopathy (MAR) syndrome.

MATERIALS AND METHODS

We reviewed the clinical and immunologic findings of 62 MAR syndrome patients. They include 25 patients from our institution (11 not previously reported) and 37 patients reported from other institutions.

RESULTS

There were 33 men and seven women (no gender information is available for the remaining 22 cases). Age at onset of the visual disturbance averaged 57.5 years (range, 30-78). Visual acuity of 20/60 or better was initially present in 82%. Fundus examination was normal in 44%, optic disc pallor was present in 23%, and retinal vessel attenuation was present in 30%. Vitreous cells were present in 30%. The latency from melanoma diagnosis to recognition of MAR syndrome averaged 3.6 years (range, 2 months to 19 years). Seven patients sustained visual improvement with various treatment regimens, especially with intravenous immunoglobulin and cytoreductive surgery (metastasectomy). Indirect immunohistochemical staining of the bipolar layer was typical, but several other retinal elements were also reactive. Tissue from a metastatic melanoma excised from one of the patients expressed antigens that reacted with antiretinal antibodies.

CONCLUSION

MAR syndrome demonstrates diverse clinical and immunologic features. Treatment, especially intravenous immunoglobulin and cytoreductive surgery (metastasectomy), improves vision in some cases.

Therapeutic apheresis in multiple sclerosis and other central nervous system disorders

Although the cause of multiple sclerosis (MS) remains unknown, the recent advances in research and the use of immunomodulating therapies have revolutionalized the way this disease is now approached. Apheresis is but one of the various immunomodulating therapies successfully used in MS. Pilot and double-blind randomized controlled studies, long-term follow-up studies, and the possible mechanism of action of therapeutic apheresis in MS are discussed. Based on our current knowledge, as well as on the available published data, it is concluded that apheresis is an effective therapy in severely progressive MS (both acute and chronic) when conventional therapies have failed.

Cholesterol biosynthesis in normocholesterolemic patients after cholesterol removal by plasmapheresis

Plasmapheresis and low-density lipoprotein (LDL)-apheresis are recognized procedures for the treatment of hyperlipidemia resistant to diet and lipid-lowering drugs and provide information on cholesterol synthesis in hypercholesterolemic patients. However, cholesterol synthesis after acute cholesterol removal from plasma has never been investigated in normocholesterolemic patients. In this study, cholesterol synthesis was evaluated in three normocholesterolemic patients by determination of plasma lathosterol, lathosterol-to-cholesterol ratio, and plasma mevalonic acid. In a short-term kinetic study, samples were collected before and after plasmapheresis and every 6 hours during 24 hours. In the second part of the study, cholesterol synthesis was evaluated daily for 3 days. In normocholesterolemic patients, cholesterol returns to basal levels in 3 days. However, cholesterol removal did not result in a significant increase in lathosterol-to-cholesterol ratio or in plasma mevalonic acid, despite a slight increase in lathosterol. In contrast, when repeated plasma exchanges induced a dramatic hypocholesterolemia (< 1 mmol/liter), an acute but transient stimulation of cholesterol synthesis was observed (lathosterol/cholesterol ratio and MVA, respectively, increase from 8.2 to 22.3 and from 28 nmol/liter to 98 nmol/liter). This study shows that cholesterol synthesis is not stimulated by plasmapheresis in normocholesterolemic patients but is enhanced in dramatic hypocholesterolemic patients (< 1 mmol/liter).

Clinical evaluation of a staphylococcal protein A immunoadsorption system in the treatment of myasthenia gravis patients

BACKGROUND

The role of plasma exchange is well established in the management of myasthenia gravis, an autoimmune disorder characterized by muscle weakness and caused by circulating IgG antibodies with specificity against the acetylcholine receptor. Plasma antibody removal by conventional means, however, is nonselective and uses replacement fluids (chiefly, albumin solution) derived from human plasma.

STUDY DESIGN AND METHODS

The Canadian Apheresis Group undertook a study at two Canadian apheresis centers to clinically evaluate a staphylococcal protein A immunoadsorption system (EXCORIM) in myasthenia gravis patients.

RESULTS

The immunoadsorption system was safe and well tolerated. Ten of 12 patients had improvement in their neurologic status, as measured by a 20-point scoring system. The mean improvement in the weakness score was significant for the group (p = 0.0013).

CONCLUSION

Patients with myasthenia gravis respond to treatment with plasma immunoadsorption. Further studies are required for a cost-benefit analysis.

Frequency of immediate adverse effects associated with therapeutic apheresis

BACKGROUND

Therapeutic apheresis was found to be reasonably safe in prior studies using instruments that are now largely obsolete. The incidence of adverse effects with current instruments and techniques has not been assessed in a large multicenter study.

STUDY DESIGN AND METHODS

A survey was conducted in 1995 using a uniform questionnaire that asked about 32 specific events but excluded transient paresthesia and mild vasovagal events. Eighteen centers returned 3429 responses concerning 125 to 500 therapeutic apheresis procedures per center.

RESULTS

Two hundred forty-two adverse events were reported in 163 procedures (4.75% of all procedures; 6.87% of first-time procedures and 4.28% of repeat procedures). The numbers (incidence) of selected specific events were transfusion reaction, 56 (51 in plasma exchange [PE] with plasma replacement) (1.6%); citrate-related nausea and/or vomiting, 41 (1.2%); systolic blood pressure <80 mmHg, 34 (1.0%); vasovagal nausea and/or vomiting, 17 (0.5%); pallor and/or diaphoresis, 16 (0.5%); pulse >120, 14 (0.4%); respiratory distress, 9 (0.3%); tetany or seizure, 9 (0.2%); and chills or rigors, 6 (0.2%). Rates for other specific events were < or =0.1 percent. Vasovagal phenomena were more frequent in procedures done in neurologic patients than in those done in hematology or oncology patients (p = 0.011) or renal or rheumatic patients (p = 0.038). Procedure-specific rates were red cell exchange, 8 (10.26%) of 78; PE (plasma), 89 (7.81 %) of 1140; PE (no plasma), 42 (3.35%) of 1255; leukapheresis, 4 (5.71%) of 70; plateletpheresis, 0 of 18; and autologous peripheral blood progenitor cell collection, 11 (1.66%) of 664. Three deaths were reported; all were attributed to primary disease.

CONCLUSION

Therapeutic apheresis procedures are relatively safe, with a 4.75-percent overall incidence of mostly reversible adverse effects. Among the most commonly performed procedures, the risk is higher for blood component exchanges, especially if allogeneic red cell or plasma transfusion occurs, and lower for peripheral blood progenitor cell collection.

Indications for emergency apheresis procedures

Therapeutic apheresis has gained tremendous popularity worldwide in the last 2 decades. Emergency procedures can be life saving but should be undertaken for limited indications. Our emergency indications and experiences since the 1970s are critically described.

Plasma-Exchange in Chronic Peripheral Neurological Disorders

We investigated 19 patients affected by chronic peripheral neurological disorders treated with therapeutic plasma exchange (TPE) to verify the efficacy of the therapeutic protocol used in these diseases.

Every patient was clinically considered after 5 TPE. Those who showed an improvement started chemotherapy and continued TPE at the rate of 2 procedures/week for 2 weeks, then 1 procedure/week for 1 month and finally 1 procedure every 2 weeks for 2 months. Intravenous immunoglobulins (IVIg) were infused at the end of apheretic treatment in one of the patients affected by neurological disorders due to monoclonal gammopathy undetermined significance. HCV-positive patients with cryoglobulins were treated with α-interferon (α-IFN) for 6 months before TPE.

Eleven patients (58%) had a symptomatic improvement, 2 (1.5%) stopped TPE treatment owing to side effects and 6 (31.5%) did not respond to apheretic therapy.

In order to improve the advantages of TPE we suggest using IVIg at the end of apheretic therapy, while in HCV-positive patients, at least one year of α-IFN therapy is required before initiating TPE.

Meta-analysis of clinical studies of the efficacy of plasma exchange in the treatment of chronic progressive multiple sclerosis

OBJECTIVE

To examine the hypothesis that addition of therapeutic plasma exchange (TPEX) to an immunosuppressive drug regimen increases that regimen's efficacy to halt the progression of chronic progressive multiple sclerosis (CPMS).

METHODS

The literature was searched for prospective controlled clinical trials evaluating the efficacy of TPEX in CPMS. Six studies were eligible for meta-analysis. Their results were combined, using Cochran's and Peto's methods. Three outcome measures were studied: 1) the change in Kurtzke's disability status scale (DSS) scores, 2) the relative odds of neurologic decline by 1 or more DSS grades, and 3) the relative odds of neurologic improvement by 1 or more DSS grades, in the treatment versus the comparison group of patients. Reported results of neurologic evaluations at 6, 12, 24, and 36 months of follow-up were analyzed separately.

RESULTS

TPEX significantly (P < .05) reduced the proportion of patients who experienced neurologic decline (by 1 or more DSS grades) at 12 months of follow-up (relative odds of decline = 0.441, 95% confidence interval = 0.210-0.929).

CONCLUSIONS

There is a need for further clinical research into the possibility of a beneficial effect of TPEX in patients with CPMS likely to experience neurologic decline over the ensuring 12 months. Targeting treatment to a particular subgroup of CPMS patients may be necessary for TPEX to prove effective.